What is the difference between diegetic and non-diegetic sound?

• A. Diegetic sound comes from a source in the scene, while non-diegetic sound is added in postproduction.
• B. Diegetic sound is always music; non-diegetic is always dialogue.
• C. Diegetic sound is only natural sounds; non-diegetic is artificial.
• D. Diegetic sound is external commentary; non-diegetic is internal thoughts.

Answer: (A)

The main idea is about where the sound comes from in relation to the story world. Diegetic sound has a source inside the film’s world—something the characters could hear or be aware of, like footsteps, dialogue between characters, or a radio playing within the scene. Non-diegetic sound, by contrast, is added for the audience and isn’t heard by the characters in the story; it includes things like a musical score or a voice-over narration that exist outside the world of the characters. This difference matters because it helps the audience understand what’s happening on screen and how the story is being shaped—diegetic sound grounds us in the scene, while non-diegetic sound signals mood, commentary, or perspective that isn’t part of the characters’ experience.